The invention relates generally to articles having an aluminum nitride coating provided by chemical vapor deposition, and more particularly to heating units, wafer carriers, and electrostatic chucks having such a coating.
The manufacture of computer integrated circuits (computer chips) requires deposition and selective removal of many layers of material. Various components are used in the equipment that applies these thin films to silicon wafers. They include heating elements, electrostatic chucks, and wafer carriers.
During wafer coating, some of the materials that are applied to the wafer or chip also deposit on the equipment in the deposition chamber, such as the heating equipment. This requires periodic cleaning of the equipment, which is commonly done using high energy gas plasma. The most aggressive plasma uses a At fluorine-bearing gas such as NF3. This produces a fluorine plasma, which cleans the chamber but also attacks the components of the equipment. This erosion limits the life of the components and the equipment. It would be desirable to extend the service life of components and equipment by use of a suitably durable coating.
A coated article is provided. The coated article may be a heating element, electrostatic chuck, or wafer carrier. The article has a body containing a substrate and a graphite element, and also has an outer coating of aluminum nitride provided by chemical vapor deposition. The outer coating protects the article against chemical attack, for example by fluorine plasma.